When making a trapped double chest with one or both named, the chests will link as a double chest when opened in spectator mode.
1: Put down a named Trapped Chest
2: Put down a named or unnamed Trapped Chest next to it
3: /gamemode sp
4: open the chests individually
Confirmed. In Spectator Mode, each side opens individually. Interestingly, you can see the title/name of each side individually as well (which normally only one shows), but the error is still there.